Why did the USA lose the Vietnam War?

1. US military tactics in Vietnam-
I thought that the U.S's tactics in Vietnam were unknown. The U.S went into Vietnam without a plan of action, they knew what they wanted but they didnt know how to defeat the Gurilla Warfare that they were against. The U.S had good weapons and trained soldiers but they could not figure out what to do with what they had, which is why they just bombed the heck out of everything. In source 39 in the Vietnam pdf file it shows the increase in the troops in Vietnam under different Presidents, it also shows the causilitys of U.S troops there. In Source 40 in the Vietnam pdf it is a discussing of a officer of the Marine Corps talking to one of his troops about how he doesnt know how the U.S is going to win this war.
2. The unpopularity of the South Vietnamese regime-
The U.S lost respect from the Vietnamese people when they appointed Diem as the leader of South Veitnam. Diem hated communism so the U.S though it would help their people oppose it to, but Diem was a really bad man who appointed his family into powerful postions and treeated the people like dirt. In source 33 in the Vietnam pdf file it shows a buddist prist burning himself to death becasue the buddish shrines were being burned by Diem (who did not like Buddists.)
3. The experience of the Viet Cong and the inexperience of the American soldiers-
The Vietcong had the home field advantage knowing the forests that they were hidding in, they also had thoes underground hideouts to avoid teh U.S troops and bombs. The Vietcong had better moral than the U.S soldiers, even though their weapons werent as advanced (backed by China and the USSR.) The U.S troops had no way of finding the Vietcong because of the Gurilla warfare and they blended in with the villiagers. The U.S lost support from the people there and other countrys becasue of all the civilan causlaties during the war. In source 36 it shows a picture of the tunnelish caves the Vietcong had, source 43 shows why the troops were sent home ( died in the first month or were sent home after a year which was just when they were gaining experience, and the commanders were stuck with a whole new spatoon again.)
4. Domestic opposition to the war in the U.S.-
People in the United States were not happy with the war, they felt that they were losing their sons, brothers, fathers to the war who were being killed by the thousands. In sources 43 it shows how fast troops were killed, and in source 36 it shows the anmount of deaths. Sources
5. Chinese and Soviet support for the Viet Cong-
The Chinses and USSR wanted the Vietcong to win becasue they were pro communist. The Chinese and Soviet Union were also supplying them with war supplies like food, ammo, and weapons. In source 38 it shows that the Chinese want to get imperilasim out of Vietnam.
6. 'But did they really lose?' Summarize the argument put forward in Source 57, and your view on it.
I dont believe that anyone really won or lost this war. There were other battles that were not covered in this lesson that show that the U.S really did have th upper hand such as the battle of Dakto, the battle Hue, and Iadrang. The U.S was able to gain back land in South Vietnam that was taken by the Vietcong, and they were able to stop the "domino theroy" from ever happening. The Vietcong in the end still had their land in North Vietnam and the support of the Communsit powers (USSR and China) and they were able to make the U.S look bad to the world. There were no clear winners like WWII in these confrontations on the U.S and the Vietcong, they would be defeated and then move on.